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Claire Beausoleil Jean-Nicolas Ormsby Andreas Gies Ulla Hass Jerrold J. Heindel Marie Louise Holmer Pia Juul Nielsen Sharon Munn Gilbert Schoenfelder 《Chemosphere》2013
A workshop was held in Berlin September 12–14th 2012 to assess the state of the science of the data supporting low dose effects and non-monotonic dose responses (“low dose hypothesis”) for chemicals with endocrine activity (endocrine disrupting chemicals or EDCs). This workshop consisted of lectures to present the current state of the science of EDC action and also the risk assessment process. These lectures were followed by breakout sessions to integrate scientists from various backgrounds to discuss in an open and unbiased manner the data supporting the “low dose hypothesis”. While no consensus was reached the robust discussions were helpful to inform both basic scientists and risk assessors on all the issues. There were a number of important ideas developed to help continue the discussion and improve communication over the next few years. 相似文献
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Krein A Audinot JN Migeon HN Hoffmann L 《Environmental science and pollution research international》2007,14(1):3-4
Background, Aim and Scope
Current scientific studies and evaluations clearly show that an increase of urban dust loads, alone or combined with other
pollutants und certain meteorological conditions lead to different significant health effects. Premature death, increased
hospital admissions and increased respiratory symptoms and diseases as well as decreased lung function can be observed in
combination with high pollutant levels. Sensitive groups like elderly people or children and persons with cardiopulmonary
diseases such as asthma are more strongly affected. Because of the direct contact between fine particles and lung tissue more
information concerning the surface structure (mapping of toxic elements) is required.
Materials and Methods:
The NanoSims50 ion microprobe images the element composition at the surface of sub-micrometer air dust particles and documents
hot spots of toxic elements as a possible threat for human health.
Results:
The atmospheric fine dust consists of a complex mixture of organic and inorganic compounds. Heavy metals are fixed on airborn
particles in the form of hot spots in a nanometer scale. From a sanitary point of view, the hot spots consisting of toxic
elements are particularly relevant as they react directly with the lung tissues.
Discussion:
To what extent particles can penetrate the various areas of the lungs and be deposited there depends on the one hand on their
physical characteristics and on the other on breathing patterns and the anatomy of the lung, which is subject to change as
the result of growth, ageing or illness. Once inhaled, some particles can reach the pulmonary alveoli and thus directly expose
the lung tissues to toxic elements.
Conclusions:
Especially the mapping of toxic arsenic or heavy metals like copper on the dust particles shows local hot spots of pollution
in the dimension of only 50 nanometers.
Recommendations and Perspectives:
Imaging of elements in atmospheric particles with NanoSIMS will help to identify the material sources. 相似文献
3.
Gismondi E Rigaud T Beisel JN Cossu-Leguille C 《Environmental pollution (Barking, Essex : 1987)》2012,160(1):17-23
Microsporidia parasites are commonly found in amphipods, where they are often asymptomatic, vertically-transmitted and have several effects on host sexuality and behaviour. As amphipods are often used as models in ecotoxicological studies, we investigated the effect of microsporidian infections on energy reserves and defence capacities of Gammarus roeseli under cadmium stress. Only females were infected by two microsporidia parasites: Dictyocoela roeselum or Dictyocoela muelleri. In physiological conditions, microsporidia had no major effect on energy reserves and defence capacities of G.?roeseli, while under cadmium exposure, energy reserves and antioxidant defence were weaker in infected females. Moreover, higher malondialdehyde levels detected in infected females revealed that they suffered more cellular damages. Our results suggest that microsporidia may affect gammarid fitness in stressful conditions, when parasitic stress cannot be compensated by the host. Consequently, microsporidia parasites should be a factor necessary to take into account in ecotoxicology studies involving amphipods. 相似文献
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Monitoring Changes in Freshwater Macroinvertebrate Communities Along a Salinity Gradient Using Artificial Substrates 总被引:1,自引:0,他引:1
Scientists strive to develop efficient sampling protocols, reducing both the number of samples and processing time required,
which can be adapted for use in a broad range of ecosystems. We investigated the accuracy and usefulness of artificial substrates
in monitoring the impact of rising salinity on freshwater macroinvertebrate communities. We sampled seven sites along a salinity
gradient (from 0.2gL-1 to 2.6gL-1) over a 19-km stretch of the Meurthe River, in northeastern France. All other parameters remained stable in this section
of the river. Artificial substrate samples, each consisting of six liters of pebbles, were removed from the river at one-month
intervals and examined. Results obtained indicated the same qualitative impairments as those found in samples collected using
a Surber net. The use of artificial substrates was found to be a viable alternative method for assessing biological changes
in river quality due to increasing salinity disturbance when Surber sampling cannot be performed. 相似文献
5.
Tanja Eybe Jean-Nicolas Audinot Thomas Udelhoven Esther Lentzen Brahime El Adib Johanna Ziebel Lucien Hoffmann Torsten Bohn 《Chemosphere》2013,90(6):1829-1838
Environmental heavy metal contamination is a case of concern for both animal and human health. Studying the fate of metals in plant or animal tissues may provide information on pollution. In the present study, we investigated the possibility to follow the biological fate of chromium and platinum uptake in common garden snails (Helix aspersa), typically accumulating high concentrations of metals from their environment. Chromium and platinum were administered orally to snails in 5 groups (n = 25/group): control, food contaminated by ca. 2.5 μg g?1 and 19 μg g?1 chromium and 2.5 μg g?1 and 25 μg g?1 platinum, for 8 weeks. Following exposure, surviving snails were sacrificed, shell and remaining tissue investigated by ICP-MS, and shell, midgut gland and mantle by nano-secondary ion mass-spectrometry (Nano-SIMS). 12C14N-normalized platinum and 40Ca-normalized chromium measurements indicated highest enrichments in cellular vesicles of the midgut gland, and lower concentrations in mantle and shell, with significantly higher platinum and chromium concentrations in the 2 exposure groups vs. control (P < 0.05), with somewhat differing distribution patterns for chromium and platinum. Comparable results were obtained by ICP-MS, with both chromium and platinum fed snails showing drastically elevated concentrations of metals in shell (up to 78 and 122 μg g?1 dw platinum and chromium, respectively) and in other tissues (up to 200 and 1125 μg g?1 dw platinum and chromium, respectively). Nano-SIMS allowed for semi-quantitative comparison of metal fate in snail tissues, making this an interesting technique for future studies in the area of environmental pollution. 相似文献
6.
A. Krein T. Udelhoven J.-N. Audinot C. Hissler C. Guignard L. Pfister H.-N. Migeon L. Hoffmann 《Water, Air, & Soil Pollution: Focus》2008,8(5-6):495-503
The increase of traffic and the rising energy consumption mean a challenge to the air pollution control and to environmental protection. Measures of air pollution control concentrated primarily on the reduction of gaseous pollutants. However, in the field of air hygiene in Central Europe, especially the load of near-surface atmospheric dust becomes threatening to human health. A SIMS microprobe for ultra fine feature analysis is used to image the elemental composition at the surface of submicrometer urban dust particles collected at two measurement stations in the Grand Duchy of Luxembourg. The NanoSIMS 50 has been chosen because it creates one intensity image for each selected element in a high spatial resolution down to 50 nm. The atmospheric fine dust consists of a mixture of organic and inorganic compounds. The elemental composition at the surface of particles was studied using a global image segmentation technique to separate the signal from the background of the particles. The analysis of the binary intensity images was carried out using several shape and proximity measures. The patch shape complexity and distribution for industrial/urban particles were found to differ significantly from the solids collected from a forest site. We conclude that the methodology developed in the study is a reliable tool to differentiate between potential sources of airborne particulate matter. 相似文献
7.
Manipulative parasites are known to alter the spatial distribution of their intermediate hosts in a way that enables trophic
transmission to definitive hosts. However, field data on the ecological implications of such changes are lacking. In particular,
little is known about the spatial coexistence between infected prey and dead-end predators after a parasite-induced habitat
shift. Here, we used an Amphipoda (Gammarus roeseli)–Acanthocephala (Polymorphus minutus) association to investigate how infection with a manipulative parasite affects the predation risk by non-hosts within the
invertebrate community. First, we collected invertebrates by sampling various natural habitats and calculated the distribution
amplitude of amphipods according to their infection status. Infection with P. minutus significantly reduced the habitat breadth in G. roeseli, parasitised individuals being mainly found in floating materials whereas uninfected ones were widespread throughout the
sampled habitats. Second, to test if these changes also affect the risk for P. minutus to be ingested by non-hosts, we estimated the predation risk experienced by G. roeseli within the macro-invertebrate community. The habitat overlap between potential invertebrate predators and G. roeseli showed that the spatial probability of encounter was lower for P. minutus-infected amphipods than for uninfected conspecifics. For the first time, to our knowledge, a study used ecological tools
to bring field evidence for the spatial avoidance of dead-end predators in a manipulated amphipod. 相似文献
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